absolute drought

(meteorology) In Britain, a period of at least 15 consecutive days during which no measurable daily precipitation has fallen.

In the UK, this is a period of 15 days, on none of which more than 0.25 mm of rain falls. National definitions vary with climate; in Libya, droughts are recognized only after two years without rain. These arbitrary definitions give no indication of the impact of drought. See palmer drought severity index (PDSI).